Will this mirror plug directly into my existing wiring?

Yes. This mirror uses factory connector points, so it wires straight to your vehicle's existing harness without modification or adapter harnesses.

Do I need to remove the interior door panel to install this?

You'll need to access the mounting area behind the mirror. Most installs require removing the inner door panel trim to reach fasteners — refer to your service manual for the exact steps specific to your model year.

Does the heating element work independently from the power windows?

Heating function operates on your vehicle's defrost circuit. It works independently and can run without engaging power adjustment.